Statistics for occurrence #1 of “Grand Gulf” in chapter 2 of Admiral David D. Porter, The Naval History of the Civil War.:
...Carolina. Fifty-three of them were mounted at Port Royal, others at Fernandina and at the defences of New Orleans.
They were met with at Fort Henry, Fort Donelson, Island No.10, Memphis, Vicksburg, Grand Gulf and Port Hudson.
We found them up the Red River as far as the gunboats penetrated, and took possession of some of them on the cars at Duvall's Bluff, on White River, bound for Little Rock.
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